def judge(list):
    new_list=[]
    for stu in list:
        if stu[1]>=90:
            new_list.append([stu[0],stu[1],'A'])
        if stu[1]<90&stu[1]>=80:
            new_list.append([stu[0],stu[1],'B'])
        if stu[1]<80&stu[1]>=70:
            new_list.append([stu[0],stu[1],'C'])    
        else:
            new_list.append([stu[0],stu[1],'D'])    
    return new_list
